Along with its annual count of homicides, rapes, robberies and aggravated assaults, the FBI last month added a new category it will track — animal cruelty.

For years, criminologists have recognized a link between animal abuse and human violence. There seems to be a “graduation effect,” where troubled youngsters rehearse by torturing the family pet or other animals before subsequently hurting humans.

Animal abusers are five times more likely to commit acts of human violence (for example, assault and rape), four times more likely to commit property offenses (such as burglary and vandalism) and three times more likely to commit drug offenses.

Animal abusers are five times more likely to commit acts of human violence.

Serial killers frequently begin by torturing and killing animals. “Boston Strangler” Albert DeSalvo trapped dogs and cats in wooden crates and shot them with a bow and arrow. John Wayne Gacy, who murdered 33 men and boys in his suburban Chicago home, tortured turkeys by throwing balloons filled with gasoline and then igniting the birds.

Ted Bundy, who took the lives of female students on several college campuses around the country, had mutilated dogs and cats as a child.

In most cases, sadistic killers employ a version of the same methods on humans as they did on animals. Lee Malvo, one of the two DC snipers, used a slingshot and marbles to kill stray cats.

John Wayne Gacy tortured turkeys by throwing balloons filled with gasoline and then igniting the birds.Photo: Getty Images

Jeffrey Dahmer strangled and dismembered 17 men and then kept their decomposing bodies in a barrel of acid. In childhood, he would reportedly kill animals to skin and soak their bones in acid before mounting their heads on stakes in the back yard.

The FBI’s inclusion will call attention to the severity of a much neglected crime. Yet the weaknesses already existing in the National Incident–Based Reporting System database are also bound to impact negatively on the reporting of offenses against animals.

The FBI relies mainly on voluntary reports from police jurisdictions across the country, many of which refuse to cooperate. Because the number of cooperating jurisdictions varies from year to year, it is impossible to examine trends in the commission of serious crimes including animal abuse.

Another problem with the NIBRS involves the unwillingness of victims to file a report with the police. Over the period of one year, for example, only 58 hate crimes against people with disabilities were included in FBI data, yet more than 33,000 hate crimes were reported anonymously by people with disabilities to the Department of Justice. Many human crimes are vastly under-reported, but at least human victims have the capacity to report their victimization to the police.

More generally, there is also the problem of defining animal cruelty. The FBI defines cruelty as “intentionally, knowingly or recklessly taking an action that mistreats or kills any animal without just cause, such as torturing, tormenting, mutilation, maiming, poisoning or abandonment.”

This includes simple or gross neglect, intentional abuse and torture, organized abuse like dog fighting and animal sexual abuse, but this broad definition is subjective and open to interpretation.

Notwithstanding problems associated with the NIBRS, the FBI’s decision to include cruelty among serious felonies in its annual report is to be applauded. Reporting crimes against animals is sure to encourage law enforcement and the public to acknowledge the importance of efforts to reduce animal cruelty.

Repeated acts of sadistic animal abuse — especially of the family pet — can serve as a warning sign to be used to identify children who are crying out for help. We can intervene in their lives before things get worse.

Jack Levin is co-director of the Brudnick Center on Violence and Conflict at Northeastern University, and Arnold Arluke is vice president and director of research for Forensic Veterinary Investigations in Boston.

We consider for consultation requests or referrals from: law enforcement in cases suspected of criminal abuse; animal control officers in cases of unknown cause of harm or death; veterinarians seeking second opinions; and attorneys who have accepted cases for potential civil litigation.

Unfortunately, we do not have the capacity to accept the volume of case inquiries that come in from individuals. Your local veterinarian or veterinary school department of pathology should be able to assist in many cases and your local humane society, animal welfare organization or animal control officer may be able to make a referral to an appropriate resource.

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